Module org.opengis.geoapi

Package org.opengis.filter

Interface BinarySpatialOperator<R>

Type Parameters:

R - the type of resources (e.g. Feature) to filter.

All Superinterfaces:

Filter<R>, Predicate<R>, SpatialOperator<R>

@UML(identifier="BinarySpatialOperator",
     specification=ISO_19143)
public interface BinarySpatialOperator<R>
extends SpatialOperator<R>

Operator that tests whether two expressions that evaluate to geometric values satisfy the spatial relationship implied by the operator. The nature of the comparison is dependent on the operator type. A standard set of spatial operators is equal, disjoin, touches, within, overlaps, crosses, intersects, contains, beyond and BBOX.

Example: An operator of type SpatialOperatorName.OVERLAPS evaluates whether the geometric value of the first expression and the geometric value of the second expression spatially overlap.

Since:

3.1

Method Summary

Modifier and Type	Method	Description
List<Expression<R,?>>	getExpressions()	Returns the two expressions to be evaluated by this operator.
default Expression<R,?>	getOperand1()	Returns the first expression to be evaluated.
default Expression<R,?>	getOperand2()	Returns the second expression to be evaluated.
SpatialOperatorName	getOperatorType()	Returns the nature of the operator.

Methods inherited from interface org.opengis.filter.Filter

getResourceClass, test

Methods inherited from interface java.util.function.Predicate

and, negate, or

Method Details

getOperatorType

@UML(identifier="operatorType",
     obligation=MANDATORY,
     specification=ISO_19143)
SpatialOperatorName getOperatorType()

Returns the nature of the operator. A standard set of spatial operators is equal, disjoin, touches, within, overlaps, crosses, intersects, contains, beyond and BBOX.

Specified by:

getOperatorType in interface Filter<R>

Specified by:

getOperatorType in interface SpatialOperator<R>

Returns:

the nature of the operator.

getOperand1

@UML(identifier="operand1",
     obligation=MANDATORY,
     specification=ISO_19143)
default Expression<R,?> getOperand1()

Returns the first expression to be evaluated. This is the element at index 0 in the expressions list. The returned expression should be an instance of ValueReference. The expression evaluation should return one of the following type:

• A geometry instance.
• A Feature instance if the operator shall be applied to the geometric values of all the spatial properties of the resource.

This {code BinarySpatialOperator} evaluates to true if all tested spatial property values fulfill the spatial relationship implied by the operator.

Returns:

the first expression to be evaluated.

Departure from OGC/ISO standard by generalization

ISO 19143 restricts the type to ValueReference. GeoAPI relaxes this restriction by allowing arbitrary expressions.

getOperand2

@UML(identifier="operand2",
     obligation=MANDATORY,
     specification=ISO_19143)
default Expression<R,?> getOperand2()

Returns the second expression to be evaluated. This is the element at index 1 in the expressions list. The returned expression should one of the following:

• A ValueReference.
• A Literal evaluating to a geometry object.
• A Literal evaluating to an Envelope.

Returns:

the second expression to be evaluated.

Departure from OGC/ISO standard due to constraint of the Java language

ISO 19143 restricts the type to SpatialDescription, which is a union between Geometry, Envelope and ValueReference. Union has no direct equivalence in Java and is replaced by documentation in this method.

getExpressions

List<Expression<R,?>> getExpressions()

Returns the two expressions to be evaluated by this operator. The list shall contain operand 1 and operand 2 in that order.

Specified by:

getExpressions in interface Filter<R>

Returns:

a list of size 2 containing the two expressions to be evaluated.